During the latter stages of the Civil War, a gang of supposed Confederates, headed by Alex Morel (Lionel Atwill), raid all gold shipments destined for Washington from Oro Grande, California. In the first chapter, "Murder By Accident", Captain Steve Clark (Dennis Moore), is recognized as a Union Secret Service agent by Morel's accomplice Trina Dessard (Virginia Christine), and, with his friend Idaho Jones (Joe Sawyer), is ambushed in the baggage car and sent to almost certain death when the car is un-coupled and plunges down the mountainside. Leaping to safety, in order to be around for the next 12 chapters, Idaho and Steve report to Colonel Sewell (Addison Richards) in Oro Grande, and Idaho introduces himself as a Wells Fargo detective to Cathy Haines (Wanda McKay), the Oro Grande company agent. Steve and Idaho learn that the Morel raiders are only posing as Confederates, and their headquarters are at Morel's "Golden Eagle" saloon. In a raid on the hideout, Steve's brother Jim (Gene Garrick) is killed by the gang. The next victim is Confederate Army Captain Clay Randolph (Regis Toomey) who has discovered that Morel is connected with a group of Prussian spies and gives Steve a clue before he dies. The clue leads Steve to a San Francisco dive owned by Abel Rackerby (Charles Wagenheim), who, thinking he has Steve in his power, exposes the ring's activities and operation methods. Aided by the San Francisco Secret Service, Steve escapes and returns to Oro Grande, where in Chapter 13, "Golden Vengeance", he and Idaho round up the spies.

Beyond Hell's Gate Pass is territory controlled by a man who calls himself King Carter; he uses a variety of schemes to prevent the railroad from being built, for fear it will finish his control of (what he considers) his land.

A western adventure serial in 12 episodes. Buffalo Bill battles gambler Jim Rodney who is trying to scare off the townspeople so he can gain possession of a gold strike discovered in the area. A nearby Indian tribe is provoked to attack the town and the cavalry is called in.

Cowboys and a businessman compete to find lost treasure.  

A mad scientist tries to sell his formula for a dist integrating gas to foreign powers.

American, Chinese and Australian agents join forces to stop the Nazis from obtaining the formula for synthetic fuel.

In this Western, comprised of 12 chapters from a serial, Kit leads a group carrying a large gold shipment across the wild West. When the Mystery Riders attack and steal the gold, Kit is the only survivor. He later joins forces with the cavalry to retrieve it.

A madman sets out to destroy a group of Chinatown merchants.

Tom Grant has found a rich gold vein and Bart Eaton is after it. Tom's sister Mary heads for the gold fields and Eaton and his men follow. Eaton teams up with Ace Daggett who plans to doublecross him and get the gold for himself. They frame Tom for murder and then try to get him to sign over his claim. The famous scout Tex Houston is on hand, escaping the attempts on his life, saving Mary from various perils, and trying to bring in the real killer and clear Tom.

Two safaris enter the African jungle intent on finding a white girl who is the heiress to a fortune. One safari, led by Jungle Jim, wants to make sure she gets the news that she is now a rich woman. The leaders of the other safari want to kill the girl so they can try to get hold of her inheritance.

Superhero Captain America battles the evil forces of the archvillain called The Scarab, who poisons his enemies and steals a secret device capable of destroying buildings by sound vibrations.

Marjorie Temple, owner of a bus line and an apparently worthless plot of land, is set upon by rich oil speculators who know her land actually is worth millions. When they try to put her out of business for good, young race driver Burn 'em Up Barnes comes to her rescue - again and again and again.

The Dead End Kids go after a gang known as the Sea Raiders, which is sinking Allied shipping.

A young couple journeys to Mystery Island to rescue the girl's father, who is being held prisoner by the evil Captain Mephisto, a pirate from 200 years ago who uses his Transformation Machine to travel forward in time and disguise himself as one of the four owners of Mystery Island.

A master criminal called The Spider puts the famous detective's brother under a hypnotic spell and turns him against Dick.

A gang of street kids work with the FBI in their attempt to find and rescue their leader's father, a scientist who has been kidnapped by a terrorist group.

A 14-episode serial in which Mala, a Polynesian in the employ of U.S. Intelligence investigates sabotage on Clipper Island. A gang of spies causes the eruption of a volcano, for which our hero is blamed. He convinces the local Princess Melani of his innocence and helps her ward off a takeover by rival high priest Porotu.